Steve "Cyanogen" Kondik -- a Washington-area Android developer whose CyanogenMod replacement firmware is currently used by over 5 million Android users -- points out that new APIs from Google make keeping root privileges active in aftermarket mods (like CyanogenMod) less essential. He reveals:

Android 4.3 introduces some new and much needed security features which not only restrict setuid binaries on the system partition (su), but also limit the capabilities of processes. In the current architecture, even if you could get elevated privileges, you can't do anything out of the ordinary. Root in the shell via ADB is all I use, and it still works just fine.

Steve "Cyanogen" Kondik [Image Source: Google+]

In other words, Google is restricting root for security reasons. But Mr. Kondik says Android's open source make this a virtual non-issue:

This isn't a problem for me, since I use CM. When there is a situation that I'd need root, I just modify the system to accomodate what I'm trying to accomplish in a secure way.
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A few good use cases for root are:

All of these can be done without exposing root, and they can be done in a very secure way.

CyanogenMod is aiming to provide alternatives to full blown root access.

In a follow-up post, he continues to push his philosophy that deep firmware fan mods (such as his own CyanogenMod framework) are a superior alternative to using a stock ROM and simply leaving exploit-granted root privileges open. He writes:

Now you can write your app and a whole new class of applications that you couldn't do without using the root sledgehammer before. Yeah, it's harder, and you need to learn the system architecture a bit, but the result is much better and more importantly it's not a gaping security hole.
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I might be exploiting this as an opportunity to sell the ideas behind CM, but I think it's a powerful concept. If your app needs to do something that normally can't be done, you can easily bend the system to your will and do it right.

Android 4.3 cracks down on root's capabilities.

For those users who want root he reassures that he will continue to support it, writing in yet another follow-up:

Just to be clear- I have no intention of removing root from CM. What I want to see is the common use cases supported by the platform so that we can write more powerful apps.

But it's clear that he feels that leaving root open is a dangerous proposition, even for your average power-user. He also feels that regimented privilege extension via new API frameworks are a superior alternative.